New York City's Population Is Down. Or Is It?

By NICHOLAS CONFESSORE

Published: April 15, 2005

According to figures released yesterday by the United States Census Bureau, New York City lost 5,547 residents last year, bringing its population to 8,104,079 as of last July 1, down from 8,109,626. It was the city's first such decrease the bureau has recorded since 1991.

But city officials say that the numbers are almost certainly wrong and that the Big Apple is bigger than ever.

''The issuing of these numbers by the Census Bureau is the beginning of a process,'' said Rachaele Raynoff, a spokeswoman for the New York City Department of City Planning. ''We will challenge the numbers, and, at the end of the day, we believe that it will be apparent that New York has grown and will continue to grow.''

So begins an annual dance nearly as protracted and complex as -- but rather more friendly than -- the budget negotiations occupying state lawmakers upstate. As in Albany, the action is a numbers game.

Every year between its decennial counts of the nation, the Census Bureau estimates populations of America's 3,141 counties. The estimates are used to help allocate federal housing assistance and low-income tax credits, among other things.

Most counties do not quarrel with the estimates. But some -- including the five counties that make up New York City -- will push for changes, arguing that the bureau's numbers do not capture reality.

''To get these out on a timely basis, we have to have a cutoff,'' said Sam Davis, a Census Bureau analyst. ''Sometimes data comes in later, and the estimates will be changed to reflect the estimates. If we didn't do that, we'd probably still be working on the 2002 estimates.''

Last year, after challenging the bureau's estimates for the populations of Brooklyn and Queens in 2003, city officials succeeded in adding about 30,000 people to New York's rolls. For good measure, the bureau also retroactively revised its estimate of the city's population for 2001 and 2002, incorporating city officials' estimates into their own. When the bureau released the 2004 number yesterday, it revised each of the previous years' estimates yet again.

Such volatility owes to the inherent difficulty of measuring the population of a country with high levels of internal migration as well as immigration from abroad.

The Census Bureau uses two main measures of population change. The first, considered by experts to be the more reliable of the two, is the net difference between reported births and deaths in a county or state, known as ''natural increase.''

But the second, known as ''net migration,'' relies on federal tax returns, which reflect changes of address within the United States, and data from the bureau's American Community Survey, which provides samples from which the bureau estimates immigration from abroad.

Both methods, say city demographers, are less reliable in counties with large populations of illegal immigrants from abroad and with illegal immigrants who have relocated after living in other states. Such residents are less likely to file tax returns when they arrive; moreover, the survey does not always produce reliable estimates of immigration at the county level.

''If a foreign-born population is not an important component of your population, which is the case for most counties, it's not a big deal,'' said Warren Brown, a demographer at Cornell University who represents New York State in negotiations with the bureau. ''But New York City just happens to have five counties for which it is a really big deal.''

Queens and Brooklyn, he noted, pose a particular challenge, since they account for about two-thirds of the city's immigrants from abroad, legal and illegal.

According to the most recent estimates, Manhattan, Staten Island, and the Bronx all gained in population; decreases in Queens and Brooklyn accounted for the city's net loss. But city officials say that is unlikely.

''Everyone who studies New York's demographics knows you don't get big increases in Staten Island and substantial increases in Bronx and Manhattan, and no increase in Brooklyn and Queens, which lead the city in immigration and new housing,'' said Joseph Salvo, who heads the Department of City Planning's population division.

Not everyone was ready to cast doubt on the city's dip. Andrew A. Beveridge, a demographer at Queens College, said that while he was ''a little surprised to see a drop,'' given previous trends, ''it's possible finally that their estimates are finally reflecting September 11.''